Cryptogenic strokes potentially account for 40% of the 500,000 strokes which occur in the United States each year. Many of these events may be associated with a patent foramen ovale (small atrial septal defect) which permits debris in the venous circulation to cross over into the arterial circulation where it may travel to the brain. Treatment for these patients often includes open heart surgery to close the defect.
A number of prior art references are known:
U.S. Pat. No. 4,473,077, which issued to Noiles et al on Sep. 25, 1984, discloses a flexible shafted surgical stapler generally useful for anastomosis procedures;
U.S. Pat. No. 4,485,817, which issued to Swiggett on Dec. 4, 1984, teaches a stapler with flexible shaft construction having hydraulic transmission/drive means. This stapler is used primarily for anastomosis of hollow body vessels; and U.S. Pat. No. 5,042,707, which issued to Taheri on Aug. 27, 1991, relates to an articulated stapler for use in the vascular system.
However, none of the above references teaches the use of a flexible stapler for intravascular procedures such as patent foramen ovale closure or a flexible stapler suitable for these procedures.